Flushing devices are used to supply water to the water intake port or ports of outboard motors and stern drives to clean the internal passages of the motors or to provide coolant allowing the motors to be run while they are out of the water. U.S. Pat. No. 3,931,828 to Lawler and U.S. Pat. No. 4,359,063 to Carlson show flushing devices which are mechanically clamped to the gearcase of an outboard motor to provide water to water inlets formed in the sides of the gearcase. U.S. Pat. No. 3,002,488 to Guhlin shows a flushing device clamped to the outboard motor to provide water to an inlet formed on the bottom of the anti-ventilation plate.